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目的研究喉癌肿瘤相关成纤维细胞(CAFs)外泌体表达下调的miRNA-656-3p对喉癌细胞生长和侵袭能力的影响以及丹参酮ⅡA对其调控作用。方法将CAFs外泌体miRNA-656-3p表达上调,制备外泌体上清,检测其对喉癌细胞体外增殖、侵袭能力及细胞周期的影响。检测中药提取物丹参酮ⅡA是否具有类似的上调CAFs外泌体miRNA-656-3p表达的作用,其作用后的CAFs外泌体上清是否具有类似的抑制喉癌增殖和侵袭能力的功效。结果过表达miR-656-3p的CAFs外泌体上清能抑制喉癌细胞的体外增殖和侵袭能力,抑制CCND2的表达,并将喉癌细胞阻滞在G0/G1期。而丹参酮ⅡA也可以上调CAFs外泌体中miR-656-3p的表达水平,其作用后的CAFs外泌体能发挥类似的抑制喉癌细胞体外增殖和侵袭的功效。结论喉癌CAFs外泌体miRNA-656-3p的表达下调促进喉癌细胞的生长和侵袭能力,丹参酮ⅡA可上调CAFs外泌体miR-656-3p的表达,通过后者抑制喉癌细胞的生长和侵袭能力。 相似文献
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《Cirugía espa?ola》2023,101(8):548-554
IntroductionPelvic fractures due to high energy trauma present a high risk of associated injuries that compromise the functional and vital prognosis of the patients. The objective of this study was to analyze the relationship between traumatic pelvic fractures and their associated injuries according to the Tile classification.MethodsRetrospective observational study of patients who suffered traumatic pelvic fractures (Type A, B or C of the Tile classification) with concomitant associated injuries, analyzing hemoglobin levels, between 6/2013 and 1/2016.ResultsA total of 42 patients were included; of those 69% (n = 29) were males, mean age was 48 years. 45% (n = 19) suffered traffic accidents and 26.2% (n = 11) falls. There was a different proportion in pelvic injuries: Tile A (n = 15, 35.7%), B (n = 20, 47.6%), and C (n = 7, 16.6%) of cases. 54.8% (n = 23) underwent surgery, 21.4% (n = 9) needed temporary or definitive external fixation. Significant differences were found between Tile A type and scapula fractures (P=.032), and Tile B with sacral fractures (P=.033) and visceral injuries (P=.049), while there is a tendency without a statistical significal between Tile C and costal fractures. 61.9% (n = 26) needed blood transfusion; 9.5% (n = 4) presented hypovolemic shock.ConclusionsTile A pelvic fractures were associated with scapular fractures, and Tile B with transforaminal fractures of the sacrum and with visceral injuries (lungs, liver and genitourinary). The small number of Tile C prevent us to confirm an association with any pathology, although they are the ones which presnt more hemodynamically instability and thoracic injuries. 相似文献
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《Dental materials》2022,38(11):1789-1800
ObjectivesDentin microstructure undergoes changes with age and its materials properties degrade over time. In the present study, we investigate the coupled influence of increased filled tubules and decreased materials properties on the fracture behavior of human dentin.MethodsWe assume degraded materials properties are linked with increased advanced glycation end-products (AGEs) crosslinks in dentin tissue. We use morphological data of human molars to create 2D and 3D models of dentin microstructure, and utilize a phase field fracture framework to study crack growth trajectories. We construct aged dentin samples (i.e., filled tubules and degraded properties) and compare the fracture results with the samples without age-related changes.ResultsThe simulations show an increase in the number of filled tubules can deactivate the toughening mechanisms such as crack deflection and microcracking. In addition, filled tubules have adverse impacts on the ability of peritubular dentin to shield microcracking. We further show how the dentinal tubules’ orientations affect the crack surface growth. We also investigate that an increase in the AGEs level can result in increased brittleness.SignificanceThe developed model and findings of the present study provide region-dependent information on crack growth trajectories as well as more understanding of crack surface growth at the presence of filled tubules. 相似文献
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Prithvi Mohandas Rajsirish Bellal Sridharan Senthilvelan Rajagopalan 《Seminars in Arthroplasty》2022,32(2):389-397
BackgroundThe treatment of complex 3- and 4-part proximal humerus fractures (PHFs) in the elderly poses significant challenges because of osteoporosis and fracture comminution. The wide range of surgical options available is evidence of the complex nature of the injury. At present, reverse shoulder replacement is gaining popularity among shoulder surgeons for treating these difficult fractures, and the literature has shown equivalent or superior outcomes with reverse shoulder arthroplasty (RSA). We aimed to analyze the long-term results of these complex PHF treated with reverse shoulder replacement.MethodsFor this study, fractures from 39 patients with a mean age of 63.18 years who were treated with RSA for acute complex fractures of the proximal humerus in our institution between 2013 and 2019 were analyzed (n = 31, acute 4-part fractures; n = 4, acute fracture–dislocation; n = 3, fracture with irreparable cuff tear; n = 1, osteoporotic 2-part fracture). All patients had a standard reverse shoulder replacement (cemented humeral stem n = 37 and uncemented stem n = 2) surgery in a level 1 trauma center. The mean follow-up duration was 60 months (24-111 months). The clinical outcomes (Oxford Shoulder Score and Constant Shoulder Score) and the complications at 6 months, 12 months, and 24 months were analyzed.ResultsOur study found a relatively younger population, with 21 patients (53.84%) aged <66 years. Spearman's correlation showed that younger patients had better signs of improvement in Oxford Shoulder Scores at 2 years (P = .008). The average Oxford Shoulder Score was 39.12 ± 4.327, and the average Constant Shoulder Score was 67.67 on the operated side. The mean active forward elevation was 142.56 ± 22.29º, abduction was 136.538 ± 24.31º, external rotation was 27 ± 9.011º, and internal rotation was 33 ± 20.41º. The overall complication rate of 17.94% (periprosthetic infection n = 2, periprosthetic humerus fracture n = 1, and hematoma evacuation n = 4) in our study was similar to those of recent studies in the literature.ConclusionRSA provides a reliable option for PHFs and offers good results in the form of pain relief and good functional outcomes at 2 years even in a younger age group. Thus, it is fast becoming an important option in treating complex PHF, but we must be wary of the steep learning curve and the complications pertinent to this procedure. 相似文献
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目的: 研究经皮椎体后凸成形术治疗骨质疏松性胸腰椎压缩性骨折的疗效。方法: 选取2019年3月至2020年9月内蒙古科技大学包医一附院收治的68例老年性骨质疏松性椎体压缩性骨折患者为研究对象,随机分为对照组和观察组,各34例;对照组应用经皮椎体成形术治疗,观察组应用经皮椎体后凸成形术治疗,对比两种术式的效果。结果: 观察组患者治疗的总有效率为94.1 %,明显高于对照组的73.5 %(P<0.05);观察组伤椎前缘高度、伤椎后缘高度、伤椎中线高度均高于对照组(P<0.05);观察组后凸角(Cobb角)小于对照组(P<0.05),VAS、ODI评分低于对照组(P<0.05);观察组并发症发生率5.9 %低于对照组的29.4 %(P<0.05);观察组生活质量评分各项均高于对照组(P<0.05)。结论: 老年性骨质疏松性椎体压缩骨折患者应用经皮椎体后凸成形术治疗可取得良好的近期疗效,能改善病情,提升其生活质量,此治疗方案适宜在临床中推广应用。 相似文献
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BackgroundPost-operative elderly hip fracture patients require significant rehabilitation. Nandrolone is an anabolic steroid used to promote muscle growth. This study aims to examine the effect of nandrolone in improving rehabilitation and quality of life in elderly female patients with hip fractures undergoing hemiarthroplasty.MethodsThis is a double-blinded prospective randomized-controlled-trial consisting of female patients above the age of 65 with an isolated neck of femur fracture planned for a hip hemiarthroplasty. Participants were randomized into two arms of the study – 50 mg intramuscular nandrolone vs normal saline placebo administered on post-operative day 0, and weeks 2, 6 and 12. The participants were followed up across a 1-year period following the surgery. Clinical outcomes such as time taken to achieve rehabilitation milestones, distance of ambulation and thigh muscle girth, and functional scoring with SF-36 questionnaire were recorded at intervals of 2, 6 and 12 weeks, 6 months and 1 year following the surgery.ResultsThere were a total of 23 subjects with 11 in the steroid group and 12 in the placebo group. There was no significant difference in demographics and injury patterns between both groups. There was no significant difference for time taken to achieve various rehabilitation milestones and distance of ambulation. SF-36 scores on discharge and at 1-year follow-up mark were comparable. There was no difference in the complication rate between both groups.ConclusionIntra-muscular Nandrolone after hip surgery in elderly female patients does not result in short to mid-term improved rehabilitation or functional outcomes. Nandrolone did not result in increased short-term complications after hip surgery.Level of evidenceI. 相似文献